btrfs-check
Check and repair btrfs filesystem integrity
TLDR
Check a btrfs filesystem
$ sudo btrfs check [path/to/partition]
Check and repair a btrfs filesystem (dangerous)$ sudo btrfs check --repair [path/to/partition]
Show the progress of the check$ sudo btrfs check -p [path/to/partition]
Verify the checksum of each data block$ sudo btrfs check --check-data-csum [path/to/partition]
Use a specific superblock (0, 1, or 2)$ sudo btrfs check -s [n] [path/to/partition]
Rebuild the checksum tree$ sudo btrfs check --repair --init-csum-tree [path/to/partition]
Rebuild the extent tree$ sudo btrfs check --repair --init-extent-tree [path/to/partition]
SYNOPSIS
btrfs check [options] device
DESCRIPTION
btrfs check examines btrfs filesystem structures for consistency errors and can optionally repair certain types of damage. It operates on unmounted filesystems only.
The check mode is non-destructive and reports issues. The repair mode attempts fixes but carries risk of data loss if used incorrectly.
PARAMETERS
--repair
Attempt to fix detected errors (dangerous, backup first)-p, --progress
Show progress during the check--check-data-csum
Verify data block checksums-s, --super num
Use the specified superblock copy (0, 1, or 2)--init-csum-tree
Rebuild the checksum tree from scratch--init-extent-tree
Rebuild the extent tree from scratch--readonly
Run in read-only mode (default)
CAVEATS
The filesystem must be unmounted. Repair operations are dangerous and can cause data loss; always backup first. Running check on a mounted filesystem may report false errors. Tree rebuild operations are last-resort options.
SEE ALSO
btrfs(8), btrfs-rescue(8), btrfs-restore(8)